1. Field of the Invention
The present invention relates to a switch assembly having an operating knob with a depression surface projecting from a switch case, in which a return elastic force acts upon one edge of a depression working surface on the lower face of the operating knob except the center portion thereof.
2. Description of the Related Art
Fitting an illuminating lamp or a beacon lens within the aforementioned operating knob causes the return elastic force of a return spring, rubber contact of a push momentary type and so forth to act upon one edge of a depression working surface on the lower face of the operating knob except the center portion thereof. With the aforementioned switch assembly in a non-depressed state, the moment generated by the return elastic force and the deadweight of the operating knob inclines the operating knob within the switch case.
As is shown in FIG. 4 rather exaggeratedly, if depression is performed in a state where the operating knob 20 has been inclined within the switch case 22 in a non-depressed state, an upper angle portion 21 of the operating knob 20 is brought into abutment against a ceiling surface 23 of the switch case 22, or side surfaces of a head portion 25 of the operating knob 20 projecting from an operation hole 24 of the switch case 22 get rubbed against side edges of the operation hole 24, interfering with the smooth depression.